Switch



July 5, 1955 c. F. GIBSON 2,712,576

SWITCH Filed Jan. 8, 1953 F g. 4 l

I l 1 Ea 32 I 44a -30 z Clarence E Gibson 3 A INVENTOR.

9 BY ma b31093 Ammlqs "hire This invention relates to new and useful improvements in switches, and more particularly to a switch having improved structural features over that disclosed in my U. S. Patent No. 2,506,208.

The primary object of the present invention is to provide a switch for internal combustion engines on automobiles for the purpose of automatically discontinuing the supply of electric current to the ignition system when, for some reason, the oil pressure of the automobile falls below normal.

Another important object of the present invention is to provide a pressure-operated switch adapted to be operatively connected to the oil pressure line of a vehicle and having contacts which are electrically connected to the ignition circuit of a vehicle whereby a drop in the normal pressure in the oil line of the vehicle will actuate the switch to open the ignition circuit of the vehicle.

A further object of the present invention is to provide a pressure-operated switch of the aforementioned character that is extremely small and compact in structure and which involves parts that are quickly and readily assembled or disassembled for inspection, repair or replacement.

A still further aim of the present invention is to provide a pressure-operated switch that is simple and practical in construction, strong and reliable in use, etlicient and durable in operation, inexpensive to produce and service, and otherwise well adapted for the services for which the same is intended.

Tiese, together with other objects and advantages which will become subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a view partly in section and partly in elevation of the present invention;

Figure 2 is an enlarged longitudinal vertical sectional view through the center of the present invention;

Figure 3 is a transverse horizontal sectional view taken substantially on the plane of section line 3-3 of Figure 2; and

Figure 4 is a view similar to Figure 2 but showing the invention in slightly modified form.

Referring now to the drawings in detail wherein, for the purpose of illustration, there is disclosed a preferred embodiment of the present invention, the numeral represents an elongated housing including a rigid metallic lower section 12 and an upper, substantially cylindrical insulated section 14. The peripheral wall 16 of the lover section 12 is internally threaded to receivably engage the externally threaded lower end 18 of an upper section 14, whereby the sections 12 and 14 are removably secured together.

Section 12 is formed with a peripheral shoulder 20 on its inner periphery below the threaded end 16 that constitutes a seat for the marginal edge of a diaphragm Cir 2 22. The diaphragm 22 faces an inlet 24 in the bottom wall of section 12 and the marginal edge of the diaphragm is held tightly seated against the shoulder 20 by a ring element or collar 26 having a threaded peripheral edge 28 that is threaded to wall 16 under the lower end 18 of section 14.

A combined guide and support member 30 has its lower end suitably fixed within the central opening in collar 26. Member 30 extends well upwardly into section 14 and is provided with an axial bore 32 that slidably receives a switch operating plunger 34. The lower end of plunger 34 engages the upper face of diaphragm 22 and the upper end of plunger 34 terminates adjacent a cut-out portion 36 in the member 3%).

A conductive band 33 is engaged about the insulating member 36 above a shoulder 40 of member 39. The band 38 carries a stationary contact 42 that opposes a second contact 44 on the depending limb 46 of a bellcrank lever 48. The apex of lever 48 is strengthened by corner gussets St that receive a pivot pin 52. The apex of lever is disposed between a pair of outwardly projecting ears 54 formed on the member 30 and the ends of pin 52 extend through these cars to pivotally attach the lever 48 to the member 30.

The upper end 32a of bore 32 is internally threaded to receivably engage an adjusting screw 56 having a lock nut 58 threaded thereon that engages the upper end of member 30 to retain the screw 56 longitudinally adjusted relative to member A coil spring 66 is disposed in cut-out portion 36 with its lower end engaging the upper limb d2 of lever 43 and its upper end engaging screw 56 to urge the limb 62 against the lower wall of the cut-out portion 36 and against the upper end of the plunger 34% when the diaphragm 22 is flexed, as shown in Figure 2. A lug 6d on the limb 62 constitutes a retainer about which the lower end of the spring 6!": is engaged.

A pair of conductors 6-5 and 63 extend into the section 14 through an opening 7% in section 1 5.. The conductor 66 is fixed to band 38 and the conductor 68 is fixed to the conductive lever 4-3. These conductors 66 and 63 are suitably electrically connected to an electric circuit such as the circuit of an automobile, and the inlet 2 is operatively connected to the oil pressure line 72 of the automobile, as disclosed in my U. S. Patent No. 2,506,208. When the oil pressure in line 72 is at a normal safe pressure, the diaphragm 22 will flex upwardly to move plunger 34 upwardly.

As the plunger 34 is moved and retained upwardly, lever 48 will be pivoted so that contact 44 engages contact 42 to complete the circuit. If the pressure in line 72 decreases below a safe value, the diaphragm 22 will flex downwardly as the force of spring 6% will exceed the pressure in line 72 acting on diaphragm 22, and contact 44 will be spaced from contact 42 to break the circuit.

Figure 4 shows the invention in slightly modified form wherein the contact 44a is on the outer face of the limb 46a of bellcrank lever 48a. In this embodiment, the band 38 is replaced by a band 33a secured to section A contact 42a fixed to band 38a opposes the contact 44a. The switch illustrated in Figure 4 includes a diaphragm which will remain flat when the oil pressure entering the lower section of the housing is at a normal pressure. If the pressure decreases in the oil line, the diaphragm will flex downwardly and the spring 60 will urge the lever 43a to a position where contact 44a engages contact 42a. The contacts 42a and .4a are electrically connected to a signal device that will be actuated when the pressure decreases below a normal safe value.

Since the circuit closes when the pressure decreases below a normal safe value, the device may be used with magnetic type engines to ground the magneto of such engines.

Having described the invention, what is claimed is:

1. A pressure actuated switch comprising a housing having upper and lower threadedly connected sections, said lower section having a peripheral shoulder, 21 diaphragm seated on said shoulder within said lower half, a retainer collar engaged within said lower section and retaining the diaphragm engaged against said shoulder, elongated combined guide and support member carried by said collar and extending upwardly into said upper section, a first contact secured to said member, a second movable contact pivotally supported adjacent the upper end of said member and movable into and out of engagement with said first contact, a plunger slidably carried by said member for moving the movable contact into engagement with the first contact, said plunger having a lower end engaged with said diaphragm, and said lower section having an inlet under said diaphragm whereby fluid under pressure may enter the diaphragm to flex the latter and move the plunger, said member having an axial bore accommodating the plunger and a cut-out portion adjacent the upper end of said member intersecting said bore, said movable contact including an arm extending into said cut-out portion over the upper end of the plunger, and spring means in said cut-out portion urging said arm against the upper end of the plunger and the movable contact away from the first contact.

2. A pressure actuated switch comprising a housing having upper and lower thrcadedly connected sections, said lower section having a peripheral shoulder, a diaphragm seated on said shoulder within said lower half, a retainer collar engaged within said'lower section and retaining the diaphragm engaged against said shoulder, an elongated combined guide and support member carried by said collar and extending centrally into said upper section, a first contact secured to said member, a second movable contact pivotally carried by said member and movable into and out of engagement with said first contact, a plunger slidably carried by said member for moving the movable contact into engagement with the first contact, said plunger having a lower end engaged with said diaphragm, and said lower section having an inlet under said diaphragm whereby fluid under pressure may enter the diaphragm to flex the latter and move the plunger, said member having an axial bore accommodating the plunger and a cut-out portion adjacent the upper end of said member intersecting said bore, said movable contact including an arm extending into said cut-out portion over the upper end of the plunger, a coil spring located within said cut-out portion and having a lower end engaging the arm to urge the latter against the upper end of the plunger, the upper end of said bore being internally threaded, an adjusting screw threaded into the upper end of said bore and having a lower end engaging the upper end of the spring, and a lock nut threaded on said screw and engaging the upper end of said member.

3. A pressure actuated switch comprising an elongated housing having upper and lower threadedly connected sections, said lower section having an annular peripheral shoulder, a diaphragm seated on said shoulder in said lower section, a retainer collar threadedly engaged in said lower section and retaining the diaphragm engaged against said shoulder, said upper section abutting the upper surface of said collar, a combined guide and support member carried by said collar and extending upwardly into said upper section, a first contact secured to said memher, a second movable contact pivotaliy carried by said member and movable into and out of engagement with said first contact, a plunger of substantially equal cross sectional area throughout its length slidably carried by said member for moving the movable contact into engagement with the first contact, said plunger having a lower end engaged with said diaphragm, and said lower section having an inlet under said diaphragm whereby fiuid unde pressure may enter the diaphragm to flex the same and move the plunger, said member having an axial bore accommodating the plunger and a cut-out portion adjacent the upper end of said member intersecting said bore, said movable Contact including an arm extending into said cut-out portion over the upper end of the plunger, a coil spring located within said cutout portion and having a lower end engaging the arm to urge the same against tie upper end of the plunger, the upper end of said bore being internally threaded, and an adjusting screw threaded into the upper end of said bore above the cut-out portion and having a lower end engaging the upper end of the spring thereby adjusting the tension of the spring.

49 References Cited in the tile of this patent UNlTED STATES PATENTS 552,803 Williams Ian. 7, 1896 851,691 Newell Apr. 30, 1997 45 2,072,984 Haskins Mar. 9, 1937 2,136,504 Hilbert et al Nov. 15, 1938 2,428,896 Reavis Sept. 30, 1947 2,435,143 Knauth Ian. 27, 194-8 2,506,208 Gibson May 2, 1950 2,579,717 Wood Dec. 25, 1951 

